Best 60-gallon Air Compressor | Powerful Compressors for Your Shop

Welcome to our buying guide to help you find the Best 60-gallon air compressor for your needs, whether for work or your DIY projects at home, we think there’s something here for everyone. Our aim is to present you with several great 60 gallon air compressors to choose from and educate you on the facts about the specific models and compressors in general so you can make an informed decision.

If you walk away from this article having learned something new then I feel I did my job. Our goal here is provide our readers with accurate information and recommend products that we can get behind as being worthy for your hard-earned money.

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Intro | Best 60-gallon air compressor

The best 60-gallon air compressors for your workshop will depend on many factors, assuming a 60-gallon compressor is what you truly need. While the size of the receiver is important, it is not the only consideration when selecting a powerful air compressor for your shop. It is merely one of them, but 60-Gallon air compressors are a popular size.

Selecting an air compressor can be complicated by many confusing acronyms like ACFM, SCFM, and CFM. I often wonder why all these are necessary, not technically, but in sales literature. In marketing an air compressor, it makes sense to make it easy to choose your product. However, I decided to add a section that explains all the terms and the relevant considerations. I explain it in clear, understandable language and guide you in selecting the best air compressor. It follows immediately after the review of the best 60-gallon air compressors for your shop.

60 Gallon Air Compressor | DeWalt DXCMV5076055

All of them have virtually the same size motors, all are stationary units with upright receivers and run on 230 Volt single phase. However, many factors remain that we need to consider when selecting an air compressor and I’ll cover them all in the review.

We selected five of the best 60-gallon, belt driven reciprocating, powerful compressors for your shop:

• Quincy QT-54 (2V41C60VC) : 4-Cylinder belt driven, 230V, 2-stage, 60-gallon
• DeWalt DXCMV5076055 : 2-Cylinder, 2-stage, belt driven,  230V, 60-gallon
• Ingersoll Rand SS5L5 : 2-Cylinder single-stage belt driven air compressor,
• Industrial Air ILA5746080: Hi-Flo 3-cylinder single stage cast iron air compressor
• Ingersoll-Rand – 2340L5-V: 2-Cylinder Two stage cast iron air compressor

To make a fair comparison of the air compressors, one of the specifications you want to compare is the CFM ratings. Unfortunately, it was not easy to find comparable specifications because the manufacturers use different ratings. To show the confusion it creates, let’s consider the following:

• Quincy QT-54 : 15.2 ACFM at 175 PSI. Max pressure =175 PSI.
• DeWalt DXCMV5076055 : 13.5 SCFM at 175 PSI. After doing some calculations I determined the ACFM value is 14.9. Maximum pressure is 175 PSI.
• TIngersoll Rand SS5L5 — 5 ACFM at 135 PSI / 18.1 at 90 PSI. Max pressure = 135 PSI.
• Industrial Air ILA5746080 : 18.1 CFM at 90 PSI. Maximum is 155 PSI.
• Ingersoll-Rand – 2340L5 : 3 CFM at 175 PSI. Maximum is 175 PSI.

ACFM is the abbreviation of Actual Cubic Feet per Minute at the time it was tested. SCFM is the Standardized Cubic Feet per Minute measures for CFM. To compare the two, you need to convert from SCFM to ACFM. To summarize the above, the Quincy QT-54, Ingersoll Rand – SS5L5, and Industrial Air ILA5746080 deliver virtually the same flow rates. The DeWalt DXCMV5076055 and the Ingersoll-Rand – 2340L 5, closely follow the top three. For two of the air compressors, the maximum pressures differ. The Ingersoll Rand – SS5L5 and Industrial Air ILA5746080 have lower maximums at 135 and 155 PSI.

With that comparison in mind, let’s look at the air compressors in more detail.

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Quincy QT-54  — 2V41C60VC

Splash Lubricated Reciprocating 2-stage compressor — 5 HP, 230 Volt, 2-stage. Best 60-gallon Air Compressor.

IMPORTANT (Extend the Warranty) : It includes a one-year limited warranty — BUT YOU CAN EXTEND IT if you Purchase an extended warranty kit (Item# 42626) at the same time (on the same receipt) as your Quincy air compressor and it will double the package warranty to 2 years and triple the pump warranty to 3 years (on-site parts and labor included).

The extended warranty kit includes all that you’ll need for your compressor’s regular maintenance during the first three years

Features (Quincy QT-54):

• Capacitor start motor with built-in thermal overload
• Less than 5 PPM oil carry-over (blow-by) rating
• 145–175 working PSI. Max PSI is 175
• ACFM @175 PSIG @ Max. RPM = 15.2
• 4-cylinder pump design
• 30,000-hour pump life rating.
• Heavy-duty, easy-to-reach, manual ball valve
• 2-stage belt drive pump with solid cast iron cylinder
• Motor RPM: 3,450 / Pump speed is 1,310 RPM
• Finned tube intercooler for maximum cooling and increased valve life
• Aluminum head for heat dissipation
• Size : 29″ x 21″ x 64″
• Extra-capacity oil reservoir for low oil temperatures
• Cast iron fly wheel for energy efficiency and durability
• 100% duty cycle
• Splash lubricated
• UL & CSA approval on all electrical components
• ASME-coded pressure relief valves and steel tank
• Quincy recommends a 50 Amp circuit breaker along with properly sized wire. Installations may vary but all electrical work should be done through a licensed electrician
• Aluminum head for cooler operating temperatures and longer life.
• Graphite cylinder and head gaskets for positive sealing and improved performance.
• Stainless-steel, corrosion resistant reed valves with controlled lift for maximum efficiency.
• Finned-copper-tubed intercooler dissipates excess heat from the first stage of compression to the second-stage, helping to eliminate carbon build up in the head and increase valve life.
• Large, balanced cast-iron flywheel for smoother operation, angled for maximum cooling across the compressor for longer life.
• High performance, automotive-style rings allow less than 6 PPM oil carryover.
• Balanced counter-weighted crankshaft for smooth, trouble-free operation.

✓ View or download the MANUAL & the  BROCHURE for the Quincy QT-54 air compressor.

Overview

The Quincy is the only four-cylinder reciprocating air compressor of the selection with the cylinders in a V-shape. It’s rated at a 100% duty cycle, which means it is designed to run all day. The Quincy is a robust, industrial strength air compressor with industrial class bearings and two-piece connecting rods in a two-stage configuration. This four-cylinder air compressor (pump) will not be stressed by hard work.

15.2 ACFM @ 175 PSI is the only airflow figure I could find. It means the maximum flow rate available to the user is less than 15.2 CFM at its 175 PSI limits. The Quincy’s kick-in pressure is 125 PSI, that’s when the motor restarts to recover the pressure. The kick-out pressure is when the pump stops, and it is set at 155 PSI. Even though the figures are not available, it’s safe to accept that the pump has a higher flow rate between 125 and 155 PSI. I say that because the flow rate delivered by the pump gets lower as the pressure rises.

If you need a steady compressed air supply to power some air tools and do cleaning and spray painting, two factors influence your air supply choices. Firstly, on the output side, the real maximum usable pressure when using the Quincy air compressor is 125 PSI. At that pressure, the receiver still contains 68.1 cubic feet of compressed air, and the pump will start. It means that the pressure will never dip below that. Secondly, to ensure the flow rate is not influenced, it must be used at less than what the pump can deliver. Even with limited information available, it is clear that the pump will never supply less than 15.2 CFM. Therefore, I can safely recommend a maximum flow setting of 15.2 CFM while keeping the maximum pressure under 125 PSI.

To summarize that lengthy explanation, the Quincy’s maximum flow rate that will not have fluctuations in supply is 15.2 CFM. To be able to maintain that airflow you will have to keep the maximum output pressure to 125 PSI. At those levels, you will not see any fluctuations in airflow (CFM) and pressure (PSI).

The Quincy air compressor has a cast iron crankcase and cylinders. The four-cylinder V configuration maintains rigid tolerances to ensure that the pump is as efficient as possible. The rigidity ensures that there is no distortion during extended use and prolongs pump life. The interior components are splash lubricated to enhance its life expectancy. They use a high-efficiency fin-and-tube inter-cooler to reduce the air temperature going to the second stage cylinder. It ensures maximum performance and increases valve life.

The design of the valves ensures the highest possible volumetric efficiency, which makes the pump super-efficient. To give the valves maximum strength and ensure a long life, Quincy uses stainless-steel valves. It also employs an unload valve which releases the pressure in the compressor when the pump stops. It ensures the compressor does not start against pressure and therefore eases the startup load on the motor.

VIDEO | Why the Quincy QT-54 is Worth the Money

To ensure that shop dust and debris do not contaminate the intake air, an automotive style intake filter with silencer protects the compressor. The motor is a 230V single-phase unit that delivers five horsepower. I recommend a 60 Amp circuit breaker for this air compressor because the startup current will be high.

The Quincy QT-54 air compressor factory is in Bay Minette, Alabama. Quincy is a well-known brand and offers excellent support to their customers. I would love to have this powerful and robust compressor in my shop, it even looks good.

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DeWalt DXCMV5076055

Two-stage, Belt Driven, 5hp, 175 psi, 230 volt. Best 60-gallon Air Compressor.

Features:

• 13.5 SCFM @ 175 PSI
• Industrial performance delivers maximum CFM @ 175 PSI; provides enough power to operate more than one air tool or device at one time
• Low pump RPM for longer life
• 230 Volt electric motor with Thermal Overload Protection
• Patented pump design provides for a cooler running pump
• Equipped with tank pressure gauge and on/off switch
• Wire form belt guard improves compressor cooling
• Four tie down holes in platform for ease in transporting
• Shipped with synthetic blend air compressor oil for optimum performance and long life
• Patented Pump design provides for a cooler Running Pump: industrial style air intake filter; easily Accessible Oil level sight glass and Oil drain with 4” extension; low Pump RPM
• Electric motor with Thermal Overload protection: protects the motor from voltage fluctuations and magnetic starter not required
• Large capacity, 60 gallon ASME* air receiver with large ¾” air outlet port
• Equipped with Tank pressure gauge and on/off switch and wire form belt guard improves compressor cooling
• 2 year pump, 1 year all other parts warranty

✓  View or download the MANUAL for the DeWalt DXCMV5076055.

Overview

The maximum pressure of this two-cylinder two-stage DeWalt is 175 PSI. In the documentation, the only flow rate given is 15.3 CFM at 100 PSI. Specifications given on supplier websites have it as 13.5 SCFM at 175 PSI. When converting that SCFM figure to ACFM, we end up with 14.9 CFM at 175 PSI. From user feedback, it seems the cut-in pressure is 135 PSI, and the cut-out is 175 PSI. So, if the pump delivers 14.9 CFM at 175 PSI, we can expect more than 14.9 CFM at 135 PSI cut-in. Allowing for 14.5 CFM at 135 PSI will ensure that the airflow remains constant. It is perfectly fit for air tools and will support several at a time, making it perfect for any shop.

VIDEO | Learn more about the DeWalt DXCMV5076055

The DeWalt motor uses a 230 Volt single-phase connection and delivers five horsepower. The motor has a re-settable overload protector and does not need a magnetic starter. But, take note that DeWalt requires installation by a licensed electrician to ensure that the warranty is valid. The two-cylinder, two-stage pump design results in a cooler running pump. The easily accessible oil level sight glass and oil drain with 4” extension enhance maintenance tasks on the pump.

The receiver is fitted with a ¾” air outlet port. I like this because it’s the size I expect to see on a shop air compressor, it will ensure that maximum airflow is maintained. The air compressor is equipped with a tank pressure gauge and on/off switch. It’s not the average garage type air compressor for air cleaning and inflating tires, an outflow regulator is not fitted. The pump air intake has an industrial grade metal intake filter with five sound attenuation baffles, which do help to reduce air noise. An automotive style replaceable filter element protects the pump from shop debris.

The warranty given by DeWalt is two years on the pump and one year on all other parts. Coming from DeWalt, I consider it a fair warranty that will be honored by the service centers.

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Ingersoll Rand SS5L5

Single Stage belt driven 60-Gallon Air Compressor

Features:

• Durable cast-iron cylinders, heads, and frame are designed for continuous operation and extended pump life
• Oversized belt wheel provides reliable design and cooler operation
• Ingersoll Rand synthetic lubricant provides 2,000-hour oil change intervals(four times longer than mineral-based lubricants
• High-efficiency stainless steel finger valves are simple, efficient, and easy to maintain
• Manual thermal overload protection of the motor
• 18.1 CFM at 90 PSI
• Max. PSI is 135
• 230 Volt
• 22.5A at full load;
• 11.5 HP
• Single-stage oil-lubricated belt-driven
• Air Outlet Size : 1/2″

Overview

The Ingersoll Rand – SS5L5 pump will deliver 15.5 CFM to the tank at its maximum pressure of 135 PSI. At 90 PSI the flow rate is 18.1 CFM. From user feedback, it seems that the air compressor kicks in at 90 PSI and out again at about 135 PSI. A replacement regulator switch is factory set at 95 PSI on and 125 PSI off. I tend to go with the replacement unit settings, so I consider the maximum constant air supply to be 95 PSI. Airflow is rated at 15.5 CFM at 135 PSI, so we can safely rate the outflow at 15.5 CFM. It will ensure a steady supply of air with no fluctuations in throughput.

VIDEO | Ingersoll Rand SS5L5 Air Compressor

The nominal power of this motor is five Horsepower, and the pump has a durable cast iron construction. Its cast iron body is robust and distortion free to deliver a pump life of well over 5,000 hours. This pump is meant for 100% continuous duty, high-pressure operation up to 135 PSIG. Its 60-gallon vertical receiver tank is ASME approved.

It is supplied with an automatic start/stop pressure switch control, fully assembled and pre-wired for delivery. The air filter is easy to change and within easy reach. The oil sight gauge gives a clear indication of the oil level, and its oil fill port is within easy reach. The pump is filled with all season select synthetic lubricant, which is only replaced after 2,000 hours of service. It performs four times longer than petroleum-based lubricants.

The compressor has the safety features you would expect for a shop air compressor. A manual reset thermal overload protector protects the motor and a totally enclosed belt guard ensures user safety.

You will need an air pressure regulator to regulate the pressure on the output lines because this compressor does not have a built-in regulator. Only a gauge measuring the tank pressure is fitted. While you are at it, you may consider a low oil switch and electric drain for the receiver. User feedback suggests that the manual drain valve at the bottom is a pain to get at.

The following user experience may be worth considering. Though the compressor is rated at 30 AMPs, it would keep shutting off when used on a 30 Amp breaker. IR technical support recommends that the unit be hard-wired (not a plug) and that it be on a 60 Amp circuit. Doing so, will ensure that you do not have a bad experience with your IR warranty should you need it. The standard warranty is for 1 year.

Ingersoll Rand offers an All Season Select start-up kit to provide improved protection for the pump. Each kit contains all oil and filters that your compressor will need in the first year. That’s everything you need for 2,000 hours of service under normal operating conditions. When using the kit, Ingersoll Rand extends the warranty to two-years.

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Industrial Air ILA5746080

Hi-Flo Single Stage, Cast Iron, One of the best 60-Gallon Air Compressors. Low profile design makes it less top heavy than traditional vertical compressors.

Features:

• 60 gallon Vertical air compressor
• 155 Max PSI
• 20.6 CFM @ 40 PSI  /  18.1 CFM @ 90 PSI
• 5.7 Running Horsepower / 230 V / 22 A
• Super Hi-Flow Cast Iron Pump
• 2 Year Limited Warranty
• Cast-iron 3-cylinder pump provides super high air flow of 155 PSI for optimum tool performance
• A Thermal Overload Protection System protects the motor from voltage fluctuations
• Uniquely designed metal belt guard improves the cooling of the compressor pump
• Oil level sight glass allows constant oil reading with an easily accessible oil refill design
• Features a stable cast-iron cylinder body, durable Swedish stainless-steel flex leaf reed valves,
• 16 in. balanced flywheel
• Low profile 60 gallon tank distributes weight more evenly, making it less top-heavy than traditional compressors

Overview

The Industrial Air ILA5746080 has a three-cylinder single stage pump driven by a 5.7 horsepower single phase motor. The maximum pressure for this air compressor is 155 PSI. Unfortunately, the pump flow rate at that pressure is not available. The only pump output flow rates I could find was 18.1 CFM @ 90 PSI and 20.6 CFM @ 40 PSI. The compressor does not come with an output regulator, only a tank pressure gauge, so you have to decide what you will install. It’s normally done to make the system compatible with your current installation.

The documentation does not provide the cut-in/cutout settings. A replacement cutout regulator is pre-set for 125-155 PSI. This air compressor is also marketed as a Powermate, which is fitted with a 125-155 PSI regulator. Using it at those levels, I will expect that it can be used with a maximum constant pressure of 125 PSI. The maximum airflow rate of 18.1 CFM @ 90 PSI gives us no indication what the flow rate at 135 PSI will be. I guess that about 15.5 CFM should be a safe estimate. The 1/4 Inch nozzle fitting size as specified is disappointing. Another supplier specifies it as 3/8 Inch, so it seems to be a small diameter outlet. With most shop fittings being ¾” you will have to use a reducer.

The pump has a one-piece cast-iron crankcase and full cast iron cylinder body. It is a durable design with splash oil lubrication and is shipped with synthetic oil. Synthetic oil is used in a compressor to prolong the life of the pump and ensure the best performance. Special flexible stainless steel leaf valves are used to prolong the service life of the valves.

A thermal overload protection system protects the motor from voltage fluctuations to prevent costly failures. The pump is driven by a belt drive that is protected by a uniquely designed metal belt guard.

Simple maintenance tasks are easy, by simply checking the oil sight glass. Topping up the oil is done in the same way as most compressors. Industrial Air uses a 16″ balanced cast iron flywheel belt drive which is smoother and quieter than direct-drive units. Three large intake filters, with built-in silencers, provide good airflow and reduce air intake noise. The air receiver has a low profile upright design that looks fat, but it provides a sure footing and looks well balanced.

The factory warranty for residential use is one year and only 90 days for commercial use.

Tech Specs:

• Air Consumption at 40 PSI : 20.6 SCFM
• Air Consumption at 90 PSI : 18.1 SCFM
• Amperage: 20A
• Motor Type: Single Stage
• Operating Pressure : 155 PSI
• Power Type: Electric
• Pump Type: 3-Cylinder
• Running Horsepower: 5.7 HP
• Tank Capacity: 60 gal.
• Tank Construction: Cast Iron
• Tank Orientation: Vertical
• Tank Style: Stationary
• Voltage: 240V

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Ingersoll-Rand – 2340L5-V

Two-stage, cast iron, 60-gallon air compressor.

Limited Edition Patriotic Style 2340L5-V is assembled in Campbellsville, KY and features a beautiful American flag design.

Features :

• Electric driven 2-stage model
• 60 gallon vertical tank
• Designed to run at high volumes and high pressure, without interruption
• Solid, 100% cast iron construction and components
• Unsurpassed quality and reliability – millions in use!
• 5 horsepower
• Radial fins deliver 360 degree cooling of cylinders to eliminate hot spots
• 14.3 ACFM @ 175 PSIG
• Receiver: 60 vertical
• Weight: 400 pounds
• Dimensions: 32L x 21W x 69H

From Ingersoll Rand  : Engineered to meet the demanding needs of automotive service and body shops, fleet maintenance, machine shops, production and manufacturing lines, woodworking shops, dry cleaners, car washes, general maintenance/repair shops, and farms.

Overview

The 2340L5-V is designed for demanding applications in shops and industrial settings. The motor is an industrial-grade ODP motor with a 100% duty cycle. It should meet the demanding needs of automotive service and body shops, in fact, all smallish shops and farms.

The compressor runs cooler due to the integral flywheel fan and finned high-efficiency copper intercooler. It has an overhung crankshaft, precision balanced for smooth and quiet operation. The 100 percent cast iron frame and cylinders stand up to everyday use, while splash lubrication enables efficient operation and easy serviceability.

Ingersoll Rand recommends that a 50 amp 230-volt circuit should be used for this compressor. The startup current on these compressors is high, so it’s better to follow their recommendation.

This air compressor delivers 14 CFM at 175 PSI and 14.3 CFM at 90 PSI. The pressure switch is set to turn the compressor on at 145 PSI and off at 175 PSI. Therefore, you can expect to use it at 145 PSI and 14 CFM without fluctuations in airflow or waiting for it to build pressure. Although it is the lowest when compared to the other compressors, it’s enough for most shop environments.

I noticed the compressor has a shut off valve attached to the output side. From user feedback, it seems it has a ½” thread size so you will need a ½” reducer for most fittings.

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Summary | 60-Gallon Air Compressor

Regrettably, it is difficult to compare air compressors online. A proper regulated set of specifications would do wonders to ease the burden. Specs are, after all, an important consideration when buying an air compressor. Let’s hope we’ll soon see the pump airflow at maximum pressure and the cut-in and cut-out settings on all spec sheets.

I did the research for you and gave all the relevant information that should influence your decision. All of these 60-gallon air compressors can be successfully used in a shop environment. These compressors are all robust and powerful and specifications do vary, but not by much. Personally, I will weigh it up between the Quincy and the DeWalt compressors.

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What size air compressor do you need?

To determine which air compressor you need for your shop you must understand air compressor specifications. You will most likely be aware of the terms PSI and CFM. But what about SCFM @ 175 PSI and ACFM @ 135 PSI? Or Flow at 90 psi (CFM), and 20.6 CFM @ 40 PSI? Are we comparing apples to apples here? Unfortunately, none are comparable. To make a straight comparison, you have to convert some ratings. Calculators and conversion tables are available on the internet, so you do not need to understand the technical details. Just be sure that you compare compatible figures.

The two most important ratings that you will use are CFM and PSI :

• PSI is the abbreviation for Pounds per Square Inch. It measures the extent to which the air is compressed.
• CFM is the abbreviation for Cubic Feet per Minute. For a user, CFM defines how long a given compressed volume of air will maintain a given flow rate.

When the air in a cylinder is pressurized, it is compressed. The result is that more air is contained in the receiver as the pressure rises. The air compressors in this review all have 60-gallon receivers. We will work with that as an example, and determine the volume of air in the receiver as we raise the pressure. When we start, the pressure inside is atmospheric, and the receiver will contain 8.02 cubic feet of air. For the comparison, we will let the pump run till we reach the required pressure and then turn it off. When we drain the receiver, a regulator set for 20 PSI controls the outflow. We let air out at a controlled 8 CFM till the pressure drops to 20 PSI.

• At 40 PSI it will contain 21.83 cubic foot. Using it at 8 CFM, 20 PSI it will last 1.36 minutes.
• At 90 PSI it will contain 49.11 cubic foot, and it will last 4.77 minutes.
• At 135 PSI it will contain 73.67 cubic foot, and it will last 7.48 minutes.
• At 175 PSI it will contain 95.49 cubic foot, and it will last 10.57 minutes.

In this context, you may consider PSI as ‘how much’ and CFM as ‘how long’.

Remember that this is all at the outlet of the receiver. At the pump side, things seem topsy-turvy. The Ingersoll Rand – SS5L5 has a maximum pressure of 135 PSI. The flow rating given at that pressure is 15.5 CFM, and at 90 PSI it is rated as 18.1 CFM. So, what is happening here? As the pressure goes up the flow drops. It is because the flow given is that of the pump. It is not the flow available at the outlet of the receiver. As the pressure rises, the air is more compressed, so the ability of the pump to move air drops. More importantly, it is also an indication of the lowest airflow the pump will deliver.

Compressors that do not run constantly use a pressure switch. The pressure switch monitors the air pressure in the air receiver. It stops the motor when the maximum pressure is reached. As the pressure drops, it reaches the lower setting at which the switch starts the motor to re-build the pressure. It is normally referred to as the kick-in pressure. If you wish to work with a pressure that does not vary, then the kick-in pressure must be higher.

Most shop tools run at pressures lower than 100 PSI. Tire shops need compressors with a higher pressure rating of between 125 and 150 PSI. Spray painters need high, constant airflow and pressure is less important. If you have a sports shop that compresses cylinders, you need a lot more pressure. You will need to buy specialized compressors, air coolers, and air filters.

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What size air compressor do I need?

Let’s say we want to use an HVLP spray gun to spray a basecoat at 28 PSI. Most HVLP spray guns will use up 10-14 SCFM (air volume) at 40 psi. Ours use 8 CFM at 28 PSI. Some questions arise:

• Does the size of the receiver matter?
• How often will the air compressor cycle on/off while I spray?
• What must the CFM rating of the system be?
• What must the maximum pressure be?

The size of the receiver

The size of the air compressor tank (receiver) matters, consider the following example to determine why.

To determine the volume of air in the receiver at the standard atmospheric pressure, you divide the tank size in gallons by 7.48. It will give you the amount of air in cubic-feet inside that tank. Since we review 60-gallon air compressors here, we will stick to that size. They will have a capacity of 8 cubic feet air in the receiver at normal, uncompressed levels.

To see if the size of the receiver matters, let’s consider two receivers. The one is a 60-gallon air compressor, and the next is a small 4-gallon unit. Both are filled with compressed air to a maximum of 175 PSI. Once full, the input is disabled, and the containers drained at a constant flow of 8 CFM. The 60-gallon receiver will now contain 95.49 cubic feet of compressed air, and it will be consumed in 11.94 minutes. The 4-gallon receiver will hold 6.37 cubic foot and will be drained in 0.8 minutes. From this comparison, it is clear that the larger receiver will create a larger buffer of compressed air than the smaller one. So the size does matter.

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Air compressor cycle time

As air is used from the receiver, the pressure drops linearly. At a pre-set pressure, the air compressor kicks in to replenish the air removed from the receiver. Four factors will influence this cycle time; the flow rate, receiver size, latency of the setting, and the air compressor size.

To see how these factors influence the cycle time, we will use our standard 60-gallon receiver. Let’s say its pressure is allowed to drop to 90 PSI before the pump kicks in. The pump runs until the maximum is reached at 175 PSI. The flow rate at the gun is the same 8 CFM, at 28 PSI. At 175 PSI the receiver contains 95.5 cubic feet air. We drain it at 8 cubic feet per minute. After 5.8 minutes, the compressor will kick in, and this cycle will continue.

• So, we change the flow rate to 2 CFM, and now we will find the compressor waits 23.19 minutes before it kicks in. Unfortunately, 2 CFM not an option with the spray gun.
• Changing the receiver size to 10 gallons will give us a cycle time of 0.97 minutes at 8 CFM.
• To change the latency, we adjust the controls so that the compressor starts when the pressure drops to 50 PSI. Now it will take 8.53 minutes before the compressor starts up again. It will run longer to build up the pressure again, but the whole cycle will be slower. This is a viable option for the spray gun scenario if it’s possible to do it.
• Back to the original arrangement, we replace the air compressor pump with a smaller unit that delivers 7 CFM and 175 PSI. After 6.63 minutes, the compressor starts up, but now it cannot even keep up with the 8 CFM delivery. It never stops before we close the tap.

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CFM rating of the system

If your main use is to power some air tools, a lot will depend on the tools’ consumption and how many are used simultaneously. Say you have 5 tools, only 3 will run simultaneously, and that consumption will be 13 CFM. They will run for no longer than a few seconds at a time, and they need a maximum pressure of 100 PSI. A compressor that can deliver 15 CFM at 175 PSI is a good fit, but it must kick in at 110 PSI at least.

If the machines that run together add up to more than 15.5 CFM, the air compressors we review here will still do the job. The important consideration is that the machines must not run continuously. When the pump kicks in it must find time to build up the compression again.

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Maximum pressure delivered by the air compressor

Most hardware shops and air compressor dealers sell air compressors between 125 and 175 psi. But, the pressure you need is dictated by the kind of tools/equipment you use. It is usually indicated on the device or in the tool’s literature.

Most compressed air equipment need between 90 and 100 PSI. For this reason, you will most likely only need an air compressor with a minimum pressure of 110 PSI. The maximum pressure does not really matter much, it is the buffer the compressor needs. For some applications, a higher pressure is needed, like 217 or 435 psi. Sometimes even up to 2900 to 4300 PSI or more (scuba diving and paintball equipment for example).

So how much pressure do YOU need? Look at the tools or machines you use, it should state the required minimum pressure. If not, 100 psi is safe to assume for hand tools. Some shop machinery also operate at 100 to 150 PSI, but to be sure, you have to check the specs or ask the manufacturer. Remember, the average pressure demanded by the tools must be a little lower than the kick-in pressure.

3.1.  Features to consider

• 100% cast-iron construction ensures reliability and better durability.
• Splash lubrication provides a simple, reliable design, reducing the initial purchase price.
• Stainless steel finger valves eliminate corrosion while guaranteeing long service life.
• One-piece connecting rods eradicate internal adjustment.
• A low-oil monitoring device to prevent low-oil damage is an advantage.
• Separate cast cylinders in two-stage air compressors with intercoolers for better cooling and extended life.